1. Field of the Invention
The present invention generally relates to photovoltaic diodes and more particularly to the method of preparing high sensitivity photovoltaic diodes which include thin sputtered Art Pb.sub.1-x Sn.sub.x Te films.
2. Description of the Prior Art
Present techniques for the fabrication of ternary alloy materials, such as lead-tin-telluride, into sensors for use in photo-detector or -emitter diodes and the like are normally relatively complicated and expensive. Certain of said techniques use bulk crystals of lead-tin-telluride modified by annealing or other methods to form p-n junctions while others of said techniques generate relatively epitaxial film on bulk crystal to form junctions through complicated and expensive procedures. Most such procedures rely upon post-deposition techniques, particularly annealing, to develop reasonable photoelectrical characteristics in the films. Examples of these procedures and the devices formed thereby may be found in "High-Performance 8-14.mu.m Pb.sub.1-x Sn.sub.x Te Photodiodes" by Kennedy et al, pp 27ff, PROC. IEEE, January 1975. Diodes of this nature are applicable to the production of photovoltaic infrared detectors, detector arrays and emitters such as tunable lasers and the like employed in sophisticated electro-optical systems with significant and varied usages. Accordingly, it would be highly desirable to be able to provide such diodes in a simple, inexpensive manner utilizing relatively low temperature techniques and to be able to tailor their physical, chemical, electro-optical and electrical properties so as to maximize their utility for specialized applications.